1. Field of the Invention
The present invention relates to a single-dose capsule made of moulded plastic and intended for coffee and other alimentary raw materials which are used for the preparation of beverages by means of percolation.
2. Description of the Related Art
A capsule consists essentially of a casing with a frustoconical shape which is filled with coffee powder (or other powdery raw material) and has a peripheral edge onto which a sealing foil is applied. Said foil, at the time of use of the capsule in a professional and/or domestic machine for the preparation of espresso coffee and/or other hot beverages, is directed downwards, namely on the opposite side to the point of entry of the hot water under pressure into the capsule.
As a typical example of the state of the art, the Applicant cites the European patent EP-A-0 521 510 where it is envisaged forming, with the said foil, the flat bottom of the capsule and creating zones of reduced thickness so as to favour tearing of the foil at the time of preparation of the beverage, under the pressure of the water which passes through the powdery raw material in a vertical direction of flow.
The resultant percolated beverage is conveyed along inaccessible pipes inside the coffee machine and then dispensed.